Cj character table

These 12 irreducible representations account for the 12 degrees of motional freedom of HNNH. Subtracting the irreducible representations corresponding to the translation and rotation of the molecule (see Cj , character table, Table 5-2) leaves us the symmetry species of the normal modes of vibration ... 

Table 6-2. Cj, Character Table and Some Direct Piquet Representations...

Cj, character table because when x and are of the same symmetry, any linear combination of the two will also have that symmetry. Note that although both the d and orbitals transform as a, in this point group, they are not degenerate... 

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